Revision as of 19:08, 14 January 2011 by Wang420 (Talk | contribs)

% Question 1:
function[] = question1()
N1 = sin(2*pi*391.995436*[0:0.0001:1]);         %G quarter note
N2 = sin(2*pi*466.1637615*[0:0.0001:1]);        %Bflat quarter
N3 = sin(2*pi*523.2511306*[0:0.0001:1.5]);      %C dotted quarter
N4 = sin(2*pi*391.995436*[0:0.0001:1]);         %G quarter
N5 = sin(2*pi*466.1637615*[0:0.0001:1]);        %Bflat quarter
N6 = sin(2*pi*554.3652618*[0:0.0001:0.5]);      %Csharp eigth
N7 = sin(2*pi*523.2511306*[0:0.0001:2]);        %C half

rest = [0:0.0001:2.5];                         %rest half and an eigth

%smoke on the water (part a):
tune = [N1 N2 N3 N4 N5 N6 N7 N1 N2 N3 N2 N1 rest]; 

newtune = [1:1:(length(tune)/2)];
% newtune(t) = tune(2t)
for i=1:(length(tune)/2)
    newtune(1,i) = tune(1,2*i);
end

%all three parts: 
alltunes = [tune newtune newtune];

wavwrite(0.02*alltunes, 18667, 'question1.wav');


Sound file:  Media:question1.wav



% Question 2:
function[] = question2()
[y, Fs] = wavread('Beatles.wav');
y = flipud(y);
wavwrite(y, Fs, 'question2.wav');



Sound file:  Media:question2.wav
1. The repeated phrase was "number nine".
2. I couldn't hear any message in the reversed version.

Alumni Liaison

Prof. Math. Ohio State and Associate Dean
Outstanding Alumnus Purdue Math 2008

Jeff McNeal